I’m trying to reinstall StartOS on a Minisforum UM560 XT after replacing the factory 512 GB NVMe SSD with a WD Black SN7100 2 TB.
Timeline
Last Thursday this same StartOS installer USB successfully installed StartOS on the factory SSD.
On Sunday the installed system booted normally and I updated StartOS.
I then replaced the factory SSD with the SN7100.
Since then I have been unable to boot the installer USB.
When I boot the installer (either via F7 Boot Menu or BIOS → Save & Exit → Boot Override), I consistently get:
Failed to open \EFI\BOOT\mmx64.efi - Not Found
Failed to load image MM: Not Found
Failed to start MokManager: Not Found
Something has gone seriously wrong: import_mok_state() failed
Things I’ve already checked:
Secure Boot is disabled (verified).
The SN7100 has been removed and carefully reseated.
The installer USB is recognized by the BIOS.
The USB contains bootx64.efi and grubx64.efi, but no mmx64.efi.
Both the F7 Boot Menu and BIOS Boot Override produce the identical error.
At this point I’m not sure whether the issue is related to the installer USB, the Minisforum UEFI, the WD SN7100, or something else.
Has anyone seen this before or have suggestions on what I should try next?
I searched the forum before posting and also did some additional troubleshooting, but I didn’t specifically work through the Guides section. I looked through the Guides again today and couldn’t find one that seemed to match this issue. If there’s a guide that applies, I’d appreciate a pointer
Before trying the workaround from your guide, I wanted to isolate whether the issue was related to the new SSD or the installer USB.
I did some additional troubleshooting:
Reinstalled the original 512 GB SSD that had previously booted StartOS successfully multiple times.
The machine still no longer boots from that SSD. It now goes directly into Aptio Setup unless I boot the installer via F7.
Completely erased the Kingston DataTraveler (diskpart clean), reflashed the same StartOS 0.4.0-beta.7 ISO with Etcher, and Etcher completed successfully with validation.
Booting the freshly flashed installer via F7 produces the exact same errors:
Failed to open \EFI\BOOT\mmx64.efi - Not Found
Failed to load image MM: Not Found
Failed to start MokManager: Not Found
Something has gone seriously wrong: import_mok_state() failed: Not Found
Since the behavior is identical with both the original 512 GB SSD and the new 2 TB WD SN7100, it doesn’t appear to depend on which SSD is installed. Reflashing and validating the installer USB also made no difference.
Given these results, do you think the next step is to follow the EFI workaround from your guide, or would you recommend something else first?
The guide isn’t connected to any particular SSD issue. As it lays out, it’s about specific hardcoded UEFI configs in Minisforums, which this guide works around. We’re guessing here (we don’t and can’t support your hardware) but it’s worth a try to see if it works.
I wanted to follow up with the outcome on the Minisforum UM560 XT.
I created a Linux Mint live USB to try the EFI workaround. Mint also failed with the same four messages:
Failed to open \EFI\BOOT\mmx64.efi
Failed to load image MM
Failed to start MokManager
import_mok_state() failed
After that, I created an Ubuntu live USB. Ubuntu booted successfully. I shut Ubuntu down without intentionally modifying the BIOS, EFI partition, or either SSD.
After shutting Ubuntu down, the Minisforum booted successfully from the original 512 GB StartOS SSD.
I then shut the system down, reinstalled the 2 TB SSD, and booted the same StartOS installer USB. This time the installer booted normally. I installed StartOS on the 2 TB SSD, updated it, and verified successful cold boots after a clean shutdown.
I wanted to share the sequence in case it is useful in investigating similar Minisforum boot issues.